Documentation: dt: update ti,am33xx-hsmmc swakeup workaround

Before 5b83b223 the driver was hard coding the wakeup irq to
be active low. The generic pm wakeirq does not override the active
high/low parameter, hence it must be specified correctly in the
device tree.
Mind that SDIO IRQ is active low as defined in the SDIO specification
Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt

@@ -102,7 +102,7 @@ not every application needs SDIO irq, e.g. MMC cards.
 		pinctrl-1 = <&mmc1_idle>;
 		pinctrl-2 = <&mmc1_sleep>;
 		...
-		interrupts-extended = <&intc 64 &gpio2 28 0>;
+		interrupts-extended = <&intc 64 &gpio2 28 GPIO_ACTIVE_LOW>;
 	};
 
 	mmc1_idle : pinmux_cirq_pin {